Merge branch 'akpm' (patches from Andrew)

Merge third patch-bomb from Andrew Morton:

 - more ocfs2 changes

 - a few hotfixes

 - Andy's compat cleanups

 - misc fixes to fatfs, ptrace, coredump, cpumask, creds, eventfd,
   panic, ipmi, kgdb, profile, kfifo, ubsan, etc.

 - many rapidio updates: fixes, new drivers.

 - kcov: kernel code coverage feature.  Like gcov, but not
   "prohibitively expensive".

 - extable code consolidation for various archs

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (81 commits)
  ia64/extable: use generic search and sort routines
  x86/extable: use generic search and sort routines
  s390/extable: use generic search and sort routines
  alpha/extable: use generic search and sort routines
  kernel/...: convert pr_warning to pr_warn
  drivers: dma-coherent: use memset_io for DMA_MEMORY_IO mappings
  drivers: dma-coherent: use MEMREMAP_WC for DMA_MEMORY_MAP
  memremap: add MEMREMAP_WC flag
  memremap: don't modify flags
  kernel/signal.c: add compile-time check for __ARCH_SI_PREAMBLE_SIZE
  mm/mprotect.c: don't imply PROT_EXEC on non-exec fs
  ipc/sem: make semctl setting sempid consistent
  ubsan: fix tree-wide -Wmaybe-uninitialized false positives
  kfifo: fix sparse complaints
  scripts/gdb: account for changes in module data structure
  scripts/gdb: add cmdline reader command
  scripts/gdb: add version command
  kernel: add kcov code coverage
  profile: hide unused functions when !CONFIG_PROC_FS
  hpwdt: use nmi_panic() when kernel panics in NMI handler
  ...

29 files changed, 98 insertions, 417 deletions

diff --git a/arch/alpha/include/asm/uaccess.h b/arch/alpha/include/asm/uaccess.h
index 9b0d400..c419b43 100644
--- a/arch/alpha/include/asm/uaccess.h
+++ b/arch/alpha/include/asm/uaccess.h
@@ -483,7 +483,13 @@ struct exception_table_entry
 	(pc) + (_fixup)->fixup.bits.nextinsn;			\
 })
 
-#define ARCH_HAS_SORT_EXTABLE
-#define ARCH_HAS_SEARCH_EXTABLE
+#define ARCH_HAS_RELATIVE_EXTABLE
+
+#define swap_ex_entry_fixup(a, b, tmp, delta)			\
+	do {							\
+		(a)->fixup.unit = (b)->fixup.unit;		\
+		(b)->fixup.unit = (tmp).fixup.unit;		\
+	} while (0)
+
 
 #endif /* __ALPHA_UACCESS_H */
diff --git a/arch/alpha/mm/Makefile b/arch/alpha/mm/Makefile
index c993d3f..5a98079 100644
--- a/arch/alpha/mm/Makefile
+++ b/arch/alpha/mm/Makefile
@@ -4,6 +4,6 @@
 
 ccflags-y := -Werror
 
-obj-y	:= init.o fault.o extable.o
+obj-y	:= init.o fault.o
 
 obj-$(CONFIG_DISCONTIGMEM) += numa.o
diff --git a/arch/alpha/mm/extable.c b/arch/alpha/mm/extable.c
deleted file mode 100644
index 813c9b6..0000000
--- a/arch/alpha/mm/extable.c
+++ /dev/null
@@ -1,92 +0,0 @@
-/*
- * linux/arch/alpha/mm/extable.c
- */
-
-#include <linux/module.h>
-#include <linux/sort.h>
-#include <asm/uaccess.h>
-
-static inline unsigned long ex_to_addr(const struct exception_table_entry *x)
-{
-	return (unsigned long)&x->insn + x->insn;
-}
-
-static void swap_ex(void *a, void *b, int size)
-{
-	struct exception_table_entry *ex_a = a, *ex_b = b;
-	unsigned long addr_a = ex_to_addr(ex_a), addr_b = ex_to_addr(ex_b);
-	unsigned int t = ex_a->fixup.unit;
-
-	ex_a->fixup.unit = ex_b->fixup.unit;
-	ex_b->fixup.unit = t;
-	ex_a->insn = (int)(addr_b - (unsigned long)&ex_a->insn);
-	ex_b->insn = (int)(addr_a - (unsigned long)&ex_b->insn);
-}
-
-/*
- * The exception table needs to be sorted so that the binary
- * search that we use to find entries in it works properly.
- * This is used both for the kernel exception table and for
- * the exception tables of modules that get loaded.
- */
-static int cmp_ex(const void *a, const void *b)
-{
-	const struct exception_table_entry *x = a, *y = b;
-
-	/* avoid overflow */
-	if (ex_to_addr(x) > ex_to_addr(y))
-		return 1;
-	if (ex_to_addr(x) < ex_to_addr(y))
-		return -1;
-	return 0;
-}
-
-void sort_extable(struct exception_table_entry *start,
-		  struct exception_table_entry *finish)
-{
-	sort(start, finish - start, sizeof(struct exception_table_entry),
-	     cmp_ex, swap_ex);
-}
-
-#ifdef CONFIG_MODULES
-/*
- * Any entry referring to the module init will be at the beginning or
- * the end.
- */
-void trim_init_extable(struct module *m)
-{
-	/*trim the beginning*/
-	while (m->num_exentries &&
-	       within_module_init(ex_to_addr(&m->extable[0]), m)) {
-		m->extable++;
-		m->num_exentries--;
-	}
-	/*trim the end*/
-	while (m->num_exentries &&
-	       within_module_init(ex_to_addr(&m->extable[m->num_exentries-1]),
-				  m))
-		m->num_exentries--;
-}
-#endif /* CONFIG_MODULES */
-
-const struct exception_table_entry *
-search_extable(const struct exception_table_entry *first,
-	       const struct exception_table_entry *last,
-	       unsigned long value)
-{
-        while (first <= last) {
-		const struct exception_table_entry *mid;
-		unsigned long mid_value;
-
-		mid = (last - first) / 2 + first;
-		mid_value = ex_to_addr(mid);
-                if (mid_value == value)
-                        return mid;
-                else if (mid_value < value)
-                        first = mid+1;
-                else
-                        last = mid-1;
-        }
-
-        return NULL;
-}
diff --git a/arch/ia64/include/asm/uaccess.h b/arch/ia64/include/asm/uaccess.h
index 4f3fb6cc..2189d5d 100644
--- a/arch/ia64/include/asm/uaccess.h
+++ b/arch/ia64/include/asm/uaccess.h
@@ -341,13 +341,11 @@ extern unsigned long __strnlen_user (const char __user *, long);
 	__su_ret;						\
 })
 
-/* Generic code can't deal with the location-relative format that we use for compactness.  */
-#define ARCH_HAS_SORT_EXTABLE
-#define ARCH_HAS_SEARCH_EXTABLE
+#define ARCH_HAS_RELATIVE_EXTABLE
 
 struct exception_table_entry {
-	int addr;	/* location-relative address of insn this fixup is for */
-	int cont;	/* location-relative continuation addr.; if bit 2 is set, r9 is set to 0 */
+	int insn;	/* location-relative address of insn this fixup is for */
+	int fixup;	/* location-relative continuation addr.; if bit 2 is set, r9 is set to 0 */
 };
 
 extern void ia64_handle_exception (struct pt_regs *regs, const struct exception_table_entry *e);
diff --git a/arch/ia64/mm/extable.c b/arch/ia64/mm/extable.c
index c99a41e..8f70bb2 100644
--- a/arch/ia64/mm/extable.c
+++ b/arch/ia64/mm/extable.c
@@ -5,107 +5,12 @@
  *	David Mosberger-Tang <davidm@hpl.hp.com>
  */
 
-#include <linux/sort.h>
-
 #include <asm/uaccess.h>
-#include <linux/module.h>
-
-static int cmp_ex(const void *a, const void *b)
-{
-	const struct exception_table_entry *l = a, *r = b;
-	u64 lip = (u64) &l->addr + l->addr;
-	u64 rip = (u64) &r->addr + r->addr;
-
-	/* avoid overflow */
-	if (lip > rip)
-		return 1;
-	if (lip < rip)
-		return -1;
-	return 0;
-}
-
-static void swap_ex(void *a, void *b, int size)
-{
-	struct exception_table_entry *l = a, *r = b, tmp;
-	u64 delta = (u64) r - (u64) l;
-
-	tmp = *l;
-	l->addr = r->addr + delta;
-	l->cont = r->cont + delta;
-	r->addr = tmp.addr - delta;
-	r->cont = tmp.cont - delta;
-}
-
-/*
- * Sort the exception table. It's usually already sorted, but there
- * may be unordered entries due to multiple text sections (such as the
- * .init text section). Note that the exception-table-entries contain
- * location-relative addresses, which requires a bit of care during
- * sorting to avoid overflows in the offset members (e.g., it would
- * not be safe to make a temporary copy of an exception-table entry on
- * the stack, because the stack may be more than 2GB away from the
- * exception-table).
- */
-void sort_extable (struct exception_table_entry *start,
-		   struct exception_table_entry *finish)
-{
-	sort(start, finish - start, sizeof(struct exception_table_entry),
-	     cmp_ex, swap_ex);
-}
-
-static inline unsigned long ex_to_addr(const struct exception_table_entry *x)
-{
-	return (unsigned long)&x->addr + x->addr;
-}
-
-#ifdef CONFIG_MODULES
-/*
- * Any entry referring to the module init will be at the beginning or
- * the end.
- */
-void trim_init_extable(struct module *m)
-{
-	/*trim the beginning*/
-	while (m->num_exentries &&
-	       within_module_init(ex_to_addr(&m->extable[0]), m)) {
-		m->extable++;
-		m->num_exentries--;
-	}
-	/*trim the end*/
-	while (m->num_exentries &&
-	       within_module_init(ex_to_addr(&m->extable[m->num_exentries-1]),
-				  m))
-		m->num_exentries--;
-}
-#endif /* CONFIG_MODULES */
-
-const struct exception_table_entry *
-search_extable (const struct exception_table_entry *first,
-		const struct exception_table_entry *last,
-		unsigned long ip)
-{
-	const struct exception_table_entry *mid;
-	unsigned long mid_ip;
-	long diff;
-
-        while (first <= last) {
-		mid = &first[(last - first)/2];
-		mid_ip = (u64) &mid->addr + mid->addr;
-		diff = mid_ip - ip;
-                if (diff == 0)
-                        return mid;
-                else if (diff < 0)
-                        first = mid + 1;
-                else
-                        last = mid - 1;
-        }
-        return NULL;
-}
 
 void
 ia64_handle_exception (struct pt_regs *regs, const struct exception_table_entry *e)
 {
-	long fix = (u64) &e->cont + e->cont;
+	long fix = (u64) &e->fixup + e->fixup;
 
 	regs->r8 = -EFAULT;
 	if (fix & 4)
diff --git a/arch/powerpc/sysdev/fsl_rio.c b/arch/powerpc/sysdev/fsl_rio.c
index c1cd369..f5bf38b9 100644
--- a/arch/powerpc/sysdev/fsl_rio.c
+++ b/arch/powerpc/sysdev/fsl_rio.c
@@ -606,6 +606,12 @@ int fsl_rio_setup(struct platform_device *dev)
 		if (!port)
 			continue;
 
+		rc = rio_mport_initialize(port);
+		if (rc) {
+			kfree(port);
+			continue;
+		}
+
 		i = *port_index - 1;
 		port->index = (unsigned char)i;
 
@@ -682,12 +688,6 @@ int fsl_rio_setup(struct platform_device *dev)
 		dev_info(&dev->dev, "RapidIO Common Transport System size: %d\n",
 				port->sys_size ? 65536 : 256);
 
-		if (rio_register_mport(port)) {
-			release_resource(&port->iores);
-			kfree(priv);
-			kfree(port);
-			continue;
-		}
 		if (port->host_deviceid >= 0)
 			out_be32(priv->regs_win + RIO_GCCSR, RIO_PORT_GEN_HOST |
 				RIO_PORT_GEN_MASTER | RIO_PORT_GEN_DISCOVERED);
@@ -726,7 +726,14 @@ int fsl_rio_setup(struct platform_device *dev)
 		fsl_rio_inbound_mem_init(priv);
 
 		dbell->mport[i] = port;
+		pw->mport[i] = port;
 
+		if (rio_register_mport(port)) {
+			release_resource(&port->iores);
+			kfree(priv);
+			kfree(port);
+			continue;
+		}
 		active_ports++;
 	}
 
diff --git a/arch/powerpc/sysdev/fsl_rio.h b/arch/powerpc/sysdev/fsl_rio.h
index d53407a..12dd18f 100644
--- a/arch/powerpc/sysdev/fsl_rio.h
+++ b/arch/powerpc/sysdev/fsl_rio.h
@@ -97,6 +97,7 @@ struct fsl_rio_dbell {
 };
 
 struct fsl_rio_pw {
+	struct rio_mport *mport[MAX_PORT_NUM];
 	struct device *dev;
 	struct rio_pw_regs __iomem *pw_regs;
 	struct rio_port_write_msg port_write_msg;
diff --git a/arch/powerpc/sysdev/fsl_rmu.c b/arch/powerpc/sysdev/fsl_rmu.c
index ffe0ee8..c1826de 100644
--- a/arch/powerpc/sysdev/fsl_rmu.c
+++ b/arch/powerpc/sysdev/fsl_rmu.c
@@ -481,14 +481,14 @@ pw_done:
 static void fsl_pw_dpc(struct work_struct *work)
 {
 	struct fsl_rio_pw *pw = container_of(work, struct fsl_rio_pw, pw_work);
-	u32 msg_buffer[RIO_PW_MSG_SIZE/sizeof(u32)];
+	union rio_pw_msg msg_buffer;
+	int i;
 
 	/*
 	 * Process port-write messages
 	 */
-	while (kfifo_out_spinlocked(&pw->pw_fifo, (unsigned char *)msg_buffer,
+	while (kfifo_out_spinlocked(&pw->pw_fifo, (unsigned char *)&msg_buffer,
 			 RIO_PW_MSG_SIZE, &pw->pw_fifo_lock)) {
-		/* Process one message */
 #ifdef DEBUG_PW
 		{
 		u32 i;
@@ -496,15 +496,19 @@ static void fsl_pw_dpc(struct work_struct *work)
 		for (i = 0; i < RIO_PW_MSG_SIZE/sizeof(u32); i++) {
 			if ((i%4) == 0)
 				pr_debug("\n0x%02x: 0x%08x", i*4,
-					 msg_buffer[i]);
+					 msg_buffer.raw[i]);
 			else
-				pr_debug(" 0x%08x", msg_buffer[i]);
+				pr_debug(" 0x%08x", msg_buffer.raw[i]);
 		}
 		pr_debug("\n");
 		}
 #endif
 		/* Pass the port-write message to RIO core for processing */
-		rio_inb_pwrite_handler((union rio_pw_msg *)msg_buffer);
+		for (i = 0; i < MAX_PORT_NUM; i++) {
+			if (pw->mport[i])
+				rio_inb_pwrite_handler(pw->mport[i],
+						       &msg_buffer);
+		}
 	}
 }
 
diff --git a/arch/s390/include/asm/uaccess.h b/arch/s390/include/asm/uaccess.h
index 9dd4cc4..e0900dd 100644
--- a/arch/s390/include/asm/uaccess.h
+++ b/arch/s390/include/asm/uaccess.h
@@ -79,18 +79,12 @@ struct exception_table_entry
 	int insn, fixup;
 };
 
-static inline unsigned long extable_insn(const struct exception_table_entry *x)
-{
-	return (unsigned long)&x->insn + x->insn;
-}
-
 static inline unsigned long extable_fixup(const struct exception_table_entry *x)
 {
 	return (unsigned long)&x->fixup + x->fixup;
 }
 
-#define ARCH_HAS_SORT_EXTABLE
-#define ARCH_HAS_SEARCH_EXTABLE
+#define ARCH_HAS_RELATIVE_EXTABLE
 
 /**
  * __copy_from_user: - Copy a block of data from user space, with less checking.
diff --git a/arch/s390/mm/Makefile b/arch/s390/mm/Makefile
index 2ae54ca..0aa0ad1 100644
--- a/arch/s390/mm/Makefile
+++ b/arch/s390/mm/Makefile
@@ -3,7 +3,7 @@
 #
 
 obj-y		:= init.o fault.o extmem.o mmap.o vmem.o maccess.o
-obj-y		+= page-states.o gup.o extable.o pageattr.o mem_detect.o
+obj-y		+= page-states.o gup.o pageattr.o mem_detect.o
 obj-y		+= pgtable.o pgalloc.o
 
 obj-$(CONFIG_CMM)		+= cmm.o
diff --git a/arch/s390/mm/extable.c b/arch/s390/mm/extable.c
deleted file mode 100644
index 18c8b81..0000000
--- a/arch/s390/mm/extable.c
+++ /dev/null
@@ -1,85 +0,0 @@
-#include <linux/module.h>
-#include <linux/sort.h>
-#include <asm/uaccess.h>
-
-/*
- * Search one exception table for an entry corresponding to the
- * given instruction address, and return the address of the entry,
- * or NULL if none is found.
- * We use a binary search, and thus we assume that the table is
- * already sorted.
- */
-const struct exception_table_entry *
-search_extable(const struct exception_table_entry *first,
-	       const struct exception_table_entry *last,
-	       unsigned long value)
-{
-	const struct exception_table_entry *mid;
-	unsigned long addr;
-
-	while (first <= last) {
-		mid = ((last - first) >> 1) + first;
-		addr = extable_insn(mid);
-		if (addr < value)
-			first = mid + 1;
-		else if (addr > value)
-			last = mid - 1;
-		else
-			return mid;
-	}
-	return NULL;
-}
-
-/*
- * The exception table needs to be sorted so that the binary
- * search that we use to find entries in it works properly.
- * This is used both for the kernel exception table and for
- * the exception tables of modules that get loaded.
- *
- */
-static int cmp_ex(const void *a, const void *b)
-{
-	const struct exception_table_entry *x = a, *y = b;
-
-	/* This compare is only valid after normalization. */
-	return x->insn - y->insn;
-}
-
-void sort_extable(struct exception_table_entry *start,
-		  struct exception_table_entry *finish)
-{
-	struct exception_table_entry *p;
-	int i;
-
-	/* Normalize entries to being relative to the start of the section */
-	for (p = start, i = 0; p < finish; p++, i += 8) {
-		p->insn += i;
-		p->fixup += i + 4;
-	}
-	sort(start, finish - start, sizeof(*start), cmp_ex, NULL);
-	/* Denormalize all entries */
-	for (p = start, i = 0; p < finish; p++, i += 8) {
-		p->insn -= i;
-		p->fixup -= i + 4;
-	}
-}
-
-#ifdef CONFIG_MODULES
-/*
- * If the exception table is sorted, any referring to the module init
- * will be at the beginning or the end.
- */
-void trim_init_extable(struct module *m)
-{
-	/* Trim the beginning */
-	while (m->num_exentries &&
-	       within_module_init(extable_insn(&m->extable[0]), m)) {
-		m->extable++;
-		m->num_exentries--;
-	}
-	/* Trim the end */
-	while (m->num_exentries &&
-	       within_module_init(extable_insn(&m->extable[m->num_exentries-1]), m))
-		m->num_exentries--;
-}
-#endif /* CONFIG_MODULES */
diff --git a/arch/sparc/include/asm/compat.h b/arch/sparc/include/asm/compat.h
index 830502fe..6f251c4 100644
--- a/arch/sparc/include/asm/compat.h
+++ b/arch/sparc/include/asm/compat.h
@@ -307,4 +307,11 @@ static inline int is_compat_task(void)
 	return test_thread_flag(TIF_32BIT);
 }
 
+static inline bool in_compat_syscall(void)
+{
+	/* Vector 0x110 is LINUX_32BIT_SYSCALL_TRAP */
+	return pt_regs_trap_type(current_pt_regs()) == 0x110;
+}
+#define in_compat_syscall in_compat_syscall
+
 #endif /* _ASM_SPARC64_COMPAT_H */
diff --git a/arch/sparc/include/asm/syscall.h b/arch/sparc/include/asm/syscall.h
index 49f71fd..1757cd6 100644
--- a/arch/sparc/include/asm/syscall.h
+++ b/arch/sparc/include/asm/syscall.h
@@ -3,6 +3,7 @@
 
 #include <uapi/linux/audit.h>
 #include <linux/kernel.h>
+#include <linux/compat.h>
 #include <linux/sched.h>
 #include <asm/ptrace.h>
 #include <asm/thread_info.h>
@@ -128,7 +129,13 @@ static inline void syscall_set_arguments(struct task_struct *task,
 
 static inline int syscall_get_arch(void)
 {
-	return is_32bit_task() ? AUDIT_ARCH_SPARC : AUDIT_ARCH_SPARC64;
+#if defined(CONFIG_SPARC64) && defined(CONFIG_COMPAT)
+	return in_compat_syscall() ? AUDIT_ARCH_SPARC : AUDIT_ARCH_SPARC64;
+#elif defined(CONFIG_SPARC64)
+	return AUDIT_ARCH_SPARC64;
+#else
+	return AUDIT_ARCH_SPARC;
+#endif
 }
 
 #endif /* __ASM_SPARC_SYSCALL_H */
diff --git a/arch/um/drivers/mconsole_kern.c b/arch/um/drivers/mconsole_kern.c
index b821b13..8a6b571 100644
--- a/arch/um/drivers/mconsole_kern.c
+++ b/arch/um/drivers/mconsole_kern.c
@@ -133,7 +133,7 @@ void mconsole_proc(struct mc_request *req)
 	ptr += strlen("proc");
 	ptr = skip_spaces(ptr);
 
-	file = file_open_root(mnt->mnt_root, mnt, ptr, O_RDONLY);
+	file = file_open_root(mnt->mnt_root, mnt, ptr, O_RDONLY, 0);
 	if (IS_ERR(file)) {
 		mconsole_reply(req, "Failed to open file", 1, 0);
 		printk(KERN_ERR "open /proc/%s: %ld\n", ptr, PTR_ERR(file));
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 8b680a5..54478b7 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -28,6 +28,7 @@ config X86
 	select ARCH_HAS_ELF_RANDOMIZE
 	select ARCH_HAS_FAST_MULTIPLIER
 	select ARCH_HAS_GCOV_PROFILE_ALL
+	select ARCH_HAS_KCOV			if X86_64
 	select ARCH_HAS_PMEM_API		if X86_64
 	select ARCH_HAS_MMIO_FLUSH
 	select ARCH_HAS_SG_CHAIN
diff --git a/arch/x86/boot/Makefile b/arch/x86/boot/Makefile
index 0bf6749..b1ef9e4 100644
--- a/arch/x86/boot/Makefile
+++ b/arch/x86/boot/Makefile
@@ -12,6 +12,13 @@
 KASAN_SANITIZE			:= n
 OBJECT_FILES_NON_STANDARD	:= y
 
+# Kernel does not boot with kcov instrumentation here.
+# One of the problems observed was insertion of __sanitizer_cov_trace_pc()
+# callback into middle of per-cpu data enabling code. Thus the callback observed
+# inconsistent state and crashed. We are interested mostly in syscall coverage,
+# so boot code is not interesting anyway.
+KCOV_INSTRUMENT		:= n
+
 # If you want to preset the SVGA mode, uncomment the next line and
 # set SVGA_MODE to whatever number you want.
 # Set it to -DSVGA_MODE=NORMAL_VGA if you just want the EGA/VGA mode.
diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
index 5e1d26e..6915ff2 100644
--- a/arch/x86/boot/compressed/Makefile
+++ b/arch/x86/boot/compressed/Makefile
@@ -19,6 +19,9 @@
 KASAN_SANITIZE			:= n
 OBJECT_FILES_NON_STANDARD	:= y
 
+# Prevents link failures: __sanitizer_cov_trace_pc() is not linked in.
+KCOV_INSTRUMENT		:= n
+
 targets := vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinux.bin.lzma \
 	vmlinux.bin.xz vmlinux.bin.lzo vmlinux.bin.lz4
 
diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile
index f9fb859..6874da5 100644
--- a/arch/x86/entry/vdso/Makefile
+++ b/arch/x86/entry/vdso/Makefile
@@ -7,6 +7,9 @@ KASAN_SANITIZE			:= n
 UBSAN_SANITIZE			:= n
 OBJECT_FILES_NON_STANDARD	:= y
 
+# Prevents link failures: __sanitizer_cov_trace_pc() is not linked in.
+KCOV_INSTRUMENT		:= n
+
 VDSO64-$(CONFIG_X86_64)		:= y
 VDSOX32-$(CONFIG_X86_X32_ABI)	:= y
 VDSO32-$(CONFIG_X86_32)		:= y
diff --git a/arch/x86/include/asm/compat.h b/arch/x86/include/asm/compat.h
index acdee09..ebb102e 100644
--- a/arch/x86/include/asm/compat.h
+++ b/arch/x86/include/asm/compat.h
@@ -316,9 +316,10 @@ static inline bool is_x32_task(void)
 	return false;
 }
 
-static inline bool is_compat_task(void)
+static inline bool in_compat_syscall(void)
 {
 	return is_ia32_task() || is_x32_task();
 }
+#define in_compat_syscall in_compat_syscall	/* override the generic impl */
 
 #endif /* _ASM_X86_COMPAT_H */
diff --git a/arch/x86/include/asm/ftrace.h b/arch/x86/include/asm/ftrace.h
index 2493885..21b66db 100644
--- a/arch/x86/include/asm/ftrace.h
+++ b/arch/x86/include/asm/ftrace.h
@@ -58,7 +58,7 @@ int ftrace_int3_handler(struct pt_regs *regs);
 #define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS 1
 static inline bool arch_trace_is_compat_syscall(struct pt_regs *regs)
 {
-	if (is_compat_task())
+	if (in_compat_syscall())
 		return true;
 	return false;
 }
diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h
index 88bff6d..a969ae6 100644
--- a/arch/x86/include/asm/uaccess.h
+++ b/arch/x86/include/asm/uaccess.h
@@ -105,9 +105,8 @@ static inline bool __chk_range_not_ok(unsigned long addr, unsigned long size, un
 struct exception_table_entry {
 	int insn, fixup, handler;
 };
-/* This is not the generic standard exception_table_entry format */
-#define ARCH_HAS_SORT_EXTABLE
-#define ARCH_HAS_SEARCH_EXTABLE
+
+#define ARCH_HAS_RELATIVE_EXTABLE
 
 extern int fixup_exception(struct pt_regs *regs, int trapnr);
 extern bool ex_has_fault_handler(unsigned long ip);
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index d5fb087..adaae2c 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -25,6 +25,12 @@ OBJECT_FILES_NON_STANDARD_relocate_kernel_$(BITS).o	:= y
 OBJECT_FILES_NON_STANDARD_mcount_$(BITS).o		:= y
 OBJECT_FILES_NON_STANDARD_test_nx.o			:= y
 
+# If instrumentation of this dir is enabled, boot hangs during first second.
+# Probably could be more selective here, but note that files related to irqs,
+# boot, dumpstack/stacktrace, etc are either non-interesting or can lead to
+# non-deterministic coverage.
+KCOV_INSTRUMENT		:= n
+
 CFLAGS_irq.o := -I$(src)/../include/asm/trace
 
 obj-y			:= process_$(BITS).o signal.o
diff --git a/arch/x86/kernel/apic/Makefile b/arch/x86/kernel/apic/Makefile
index 8bb12ddc..8e63ebd 100644
--- a/arch/x86/kernel/apic/Makefile
+++ b/arch/x86/kernel/apic/Makefile
@@ -2,6 +2,10 @@
 # Makefile for local APIC drivers and for the IO-APIC code
 #
 
+# Leads to non-deterministic coverage that is not a function of syscall inputs.
+# In particualr, smp_apic_timer_interrupt() is called in random places.
+KCOV_INSTRUMENT		:= n
+
 obj-$(CONFIG_X86_LOCAL_APIC)	+= apic.o apic_noop.o ipi.o vector.o
 obj-y				+= hw_nmi.o
 
diff --git a/arch/x86/kernel/cpu/Makefile b/arch/x86/kernel/cpu/Makefile
index 0d373d7..4a8697f 100644
--- a/arch/x86/kernel/cpu/Makefile
+++ b/arch/x86/kernel/cpu/Makefile
@@ -8,6 +8,10 @@ CFLAGS_REMOVE_common.o = -pg
 CFLAGS_REMOVE_perf_event.o = -pg
 endif
 
+# If these files are instrumented, boot hangs during the first second.
+KCOV_INSTRUMENT_common.o := n
+KCOV_INSTRUMENT_perf_event.o := n
+
 # Make sure load_percpu_segment has no stackprotector
 nostackp := $(call cc-option, -fno-stack-protector)
 CFLAGS_common.o		:= $(nostackp)
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index 776229e..dfa2781 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -478,7 +478,7 @@ void set_personality_ia32(bool x32)
 		if (current->mm)
 			current->mm->context.ia32_compat = TIF_X32;
 		current->personality &= ~READ_IMPLIES_EXEC;
-		/* is_compat_task() uses the presence of the x32
+		/* in_compat_syscall() uses the presence of the x32
 		   syscall bit flag to determine compat status */
 		current_thread_info()->status &= ~TS_COMPAT;
 	} else {
diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile
index a501fa2..72a5767 100644
--- a/arch/x86/lib/Makefile
+++ b/arch/x86/lib/Makefile
@@ -2,6 +2,9 @@
 # Makefile for x86 specific library files.
 #
 
+# Produces uninteresting flaky coverage.
+KCOV_INSTRUMENT_delay.o	:= n
+
 inat_tables_script = $(srctree)/arch/x86/tools/gen-insn-attr-x86.awk
 inat_tables_maps = $(srctree)/arch/x86/lib/x86-opcode-map.txt
 quiet_cmd_inat_tables = GEN     $@
diff --git a/arch/x86/mm/Makefile b/arch/x86/mm/Makefile
index 67cf2e1..f989132 100644
--- a/arch/x86/mm/Makefile
+++ b/arch/x86/mm/Makefile
@@ -1,3 +1,6 @@
+# Kernel does not boot with instrumentation of tlb.c.
+KCOV_INSTRUMENT_tlb.o	:= n
+
 obj-y	:=  init.o init_$(BITS).o fault.o ioremap.o extable.o pageattr.o mmap.o \
 	    pat.o pgtable.o physaddr.o gup.o setup_nx.o
 
diff --git a/arch/x86/mm/extable.c b/arch/x86/mm/extable.c
index 9dd7e4b..82447b3 100644
--- a/arch/x86/mm/extable.c
+++ b/arch/x86/mm/extable.c
@@ -1,17 +1,10 @@
 #include <linux/module.h>
-#include <linux/spinlock.h>
-#include <linux/sort.h>
 #include <asm/uaccess.h>
 
 typedef bool (*ex_handler_t)(const struct exception_table_entry *,
 			    struct pt_regs *, int);
 
 static inline unsigned long
-ex_insn_addr(const struct exception_table_entry *x)
-{
-	return (unsigned long)&x->insn + x->insn;
-}
-static inline unsigned long
 ex_fixup_addr(const struct exception_table_entry *x)
 {
 	return (unsigned long)&x->fixup + x->fixup;
@@ -110,104 +103,3 @@ int __init early_fixup_exception(unsigned long *ip)
 	*ip = new_ip;
 	return 1;
 }
-
-/*
- * Search one exception table for an entry corresponding to the
- * given instruction address, and return the address of the entry,
- * or NULL if none is found.
- * We use a binary search, and thus we assume that the table is
- * already sorted.
- */
-const struct exception_table_entry *
-search_extable(const struct exception_table_entry *first,
-	       const struct exception_table_entry *last,
-	       unsigned long value)
-{
-	while (first <= last) {
-		const struct exception_table_entry *mid;
-		unsigned long addr;
-
-		mid = ((last - first) >> 1) + first;
-		addr = ex_insn_addr(mid);
-		if (addr < value)
-			first = mid + 1;
-		else if (addr > value)
-			last = mid - 1;
-		else
-			return mid;
-        }
-        return NULL;
-}
-
-/*
- * The exception table needs to be sorted so that the binary
- * search that we use to find entries in it works properly.
- * This is used both for the kernel exception table and for
- * the exception tables of modules that get loaded.
- *
- */
-static int cmp_ex(const void *a, const void *b)
-{
-	const struct exception_table_entry *x = a, *y = b;
-
-	/*
-	 * This value will always end up fittin in an int, because on
-	 * both i386 and x86-64 the kernel symbol-reachable address
-	 * space is < 2 GiB.
-	 *
-	 * This compare is only valid after normalization.
-	 */
-	return x->insn - y->insn;
-}
-
-void sort_extable(struct exception_table_entry *start,
-		  struct exception_table_entry *finish)
-{
-	struct exception_table_entry *p;
-	int i;
-
-	/* Convert all entries to being relative to the start of the section */
-	i = 0;
-	for (p = start; p < finish; p++) {
-		p->insn += i;
-		i += 4;
-		p->fixup += i;
-		i += 4;
-		p->handler += i;
-		i += 4;
-	}
-
-	sort(start, finish - start, sizeof(struct exception_table_entry),
-	     cmp_ex, NULL);
-
-	/* Denormalize all entries */
-	i = 0;
-	for (p = start; p < finish; p++) {
-		p->insn -= i;
-		i += 4;
-		p->fixup -= i;
-		i += 4;
-		p->handler -= i;
-		i += 4;
-	}
-}
-
-#ifdef CONFIG_MODULES
-/*
- * If the exception table is sorted, any referring to the module init
- * will be at the beginning or the end.
- */
-void trim_init_extable(struct module *m)
-{
-	/*trim the beginning*/
-	while (m->num_exentries &&
-	       within_module_init(ex_insn_addr(&m->extable[0]), m)) {
-		m->extable++;
-		m->num_exentries--;
-	}
-	/*trim the end*/
-	while (m->num_exentries &&
-	       within_module_init(ex_insn_addr(&m->extable[m->num_exentries-1]), m))
-		m->num_exentries--;
-}
-#endif /* CONFIG_MODULES */
diff --git a/arch/x86/realmode/rm/Makefile b/arch/x86/realmode/rm/Makefile
index 053abe7b0..b959646 100644
--- a/arch/x86/realmode/rm/Makefile
+++ b/arch/x86/realmode/rm/Makefile
@@ -9,6 +9,9 @@
 KASAN_SANITIZE			:= n
 OBJECT_FILES_NON_STANDARD	:= y
 
+# Prevents link failures: __sanitizer_cov_trace_pc() is not linked in.
+KCOV_INSTRUMENT		:= n
+
 always := realmode.bin realmode.relocs
 
 wakeup-objs	:= wakeup_asm.o wakemain.o video-mode.o